I’m about to purchase some in-wall speakers and a receiver for our new office space, which is currently being built out. It just occured to me now :smack: to look at the rated wattage for both.
The receiver I picked out (JVC RX-D301S) for its various features is rated at 110W/channel. The speakers I picked out (Polk Audio RC55i) are rated at 20W-100W/channel.
I have the option of stepping down to the JVC RX-D201S, which is rated at 100W/channel. But it’s missing a couple of the features we were hoping to take advantage of on the 301S.
So my question is, how likely am I to damage the speakers if still buy the 301S, and is it worth the risk?
dammit, hit reply too soon. I think as long as you don’t crank it up, you’re fine. I ran simlar speakers on a 150W receiver for 6 years with no problem.
You will probably be coasting along, putting no more than a few watts at office background music levels.
If anything, an underpowered amp can be more likely to damage speakers. Tweeters, especially, can be damaged if an underpowered amp can’t handle the demand and starts clipping - smooth music-shaped signals get bluntly chopped off with hard edges that can overheat speakers.
As a demo, a stereo salesman I met used to plug a car speaker directly into the wall outlet to show that simple speaker wattage ratings had little meaning.
His point was that the only meaningful power ratings were only ratings that were “power at frequency” ratings, ie: “50w at 1000Hz”.
Other than that, I’d bow to those more audiophilic that I on this board.
Yeah, you’ll be fine. At any normal listening level your amp is only putting out a fraction of its rated power, usually only a few percent. And speaker power ratings are always going to have a little “fudge-factor”. So a mismatch of 10 watts is nothing at all to worry about. You could probably use a receiver with an output rating of anywhere from 50 to 150 watts with no problem.
Longer answer:
gotpasswords is correct in that the conventional wisdom is that you are in more danger of damaging your speakers with an underpowered amp than an overpowered one. But this is only true under certain circumstances. For a longer (and possibly boring) explanation, read on.
When a solid state amp reaches its maximum output, it “clips” if you drive it any harder. Clipping means that you get very distorted output waves, including square waves. Since you are more likely to crank a lower power amp all the way up until it runs out of power, you’re more likely to overdrive it and cause it to clip.
Why do we care about clipping and square waves? Because square waves look like a signal with an infinitely high frequency.
Why do we care about signals that have an infinitely high frequency? Because most high frequency sounds in music and voice recordings are fairly low in power compared to the lower frequencies. Because of this the high frequency drivers (called tweeters) in speakers are usually only rated for a fraction of the total power, and some electronics (usually inside the speaker) called the crossover-network keeps the high power lower frequencies away from the tweeters and safely routed to the middle and low frequency drivers (midrange and woofers).
So if you send a square wave into a crossover-network, it gets routed to the tweeter. Since tweeters normally aren’t rated to handle much power, they can burn out when you suddenly sneak in a signal at the full rated power of the amp.
But notice this only happens on speakers with separate tweeters that are rated to handle significantly lower power than the overall speaker rating, and only if the crossover itself doesn’t have some current limiting capability (although with some crossovers, that current limiting function is to burn out. This may not be much better than the tweeter burning out.) With single driver speakers this isn’t a problem.
And it also only occurs with the amp driven beyond maximum, which with any reasonable combination of amp and speakers is way past background or normal listening levels for an office.
I appreciate all of the great answers! I went ahead and bought both the receiver and the speakers. And I learned something in the process…ignorance successfully fought!
It would be useful for me to realize, in the future, that this computer is set up to automatically log in to SDMB as my wife rather than as me. Please view the previous post as though it was sent by me as opposed to Jakeline.
Mods, nothing malicious intended, I assure you. Apologies.
You’re fine,as others have noted. I think the current common knowledge is that you would prefer to have 2x the speakers maximum power input as your amplifiers RMS output. This allows you to have plenty of headroom before you induce any clipped signals.
